[Payments] Do not show error on initial load of address screen

components/payments/content/payment_request_spec.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/payments/content/payment_request_spec.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 41 matching lines @@
     std::vector<mojom::PaymentMethodDataPtr> method_data,
     Observer* observer,
     const std::string& app_locale)
     : options_(std::move(options)),
       details_(std::move(details)),
       app_locale_(app_locale),
       selected_shipping_option_(nullptr),
       observer_for_testing_(nullptr) {
   if (observer)
     AddObserver(observer);
-  UpdateSelectedShippingOption();
+  UpdateSelectedShippingOption(/*after_update=*/false);
   PopulateValidatedMethodData(method_data);
 }
 PaymentRequestSpec::~PaymentRequestSpec() {}
 
 void PaymentRequestSpec::UpdateWith(mojom::PaymentDetailsPtr details) {
   details_ = std::move(details);
   // We reparse the |details_| and update the observers.
-  UpdateSelectedShippingOption();
+  UpdateSelectedShippingOption(/*after_update=*/true);
   NotifyOnSpecUpdated();
 }
 
 void PaymentRequestSpec::AddObserver(Observer* observer) {
   CHECK(observer);
   observers_.AddObserver(observer);
 }
 
 void PaymentRequestSpec::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
@@ skipping 82 matching lines @@
     method_data_vector.push_back(std::move(method_data));
   }
 
   data_util::ParseBasicCardSupportedNetworks(method_data_vector,
                                              &supported_card_networks_,
                                              &basic_card_specified_networks_);
   supported_card_networks_set_.insert(supported_card_networks_.begin(),
                                       supported_card_networks_.end());
 }
 
-void PaymentRequestSpec::UpdateSelectedShippingOption() {
+void PaymentRequestSpec::UpdateSelectedShippingOption(bool after_update) {
   if (!request_shipping())
     return;
 
+  selected_shipping_option_ = nullptr;
   selected_shipping_option_error_.clear();
+  if (details().shipping_options.empty()) {
+    // No options are provided by the merchant.
+    if (after_update) {
+      // This is after an update, which means that the selected address is no
+      // supported. The merchant may have customized the error string, or a
+      // generic one is used.
+      if (!details().error.empty()) {
+        selected_shipping_option_error_ = base::UTF8ToUTF16(details().error);
+      } else {
+        selected_shipping_option_error_ = l10n_util::GetStringUTF16(
+            IDS_PAYMENTS_UNSUPPORTED_SHIPPING_ADDRESS);
+      }
+    }
+    return;
+  }
+
   // As per the spec, the selected shipping option should initially be the last
-  // one in the array that has its selected field set to true.
+  // one in the array that has its selected field set to true. If none are
+  // selected by the merchant, |selected_shipping_option_| stays nullptr.
   auto selected_shipping_option_it = std::find_if(
       details().shipping_options.rbegin(), details().shipping_options.rend(),
       [](const payments::mojom::PaymentShippingOptionPtr& element) {
         return element->selected;
       });
   if (selected_shipping_option_it != details().shipping_options.rend()) {
     selected_shipping_option_ = selected_shipping_option_it->get();
-  } else {
-    // It's possible that there is no selected shipping option.
-    if (!details().error.empty()) {
-      selected_shipping_option_error_ = base::UTF8ToUTF16(details().error);
-    } else {
-      selected_shipping_option_error_ =
-          l10n_util::GetStringUTF16(IDS_PAYMENTS_UNSUPPORTED_SHIPPING_ADDRESS);
-    }
-    selected_shipping_option_ = nullptr;
   }
 }
 
 void PaymentRequestSpec::NotifyOnSpecUpdated() {
   for (auto& observer : observers_)
     observer.OnSpecUpdated();
   if (observer_for_testing_)
     observer_for_testing_->OnSpecUpdated();
 }
 
 CurrencyFormatter* PaymentRequestSpec::GetOrCreateCurrencyFormatter(
     const std::string& currency_code,
     const std::string& currency_system,
     const std::string& locale_name) {
   if (!currency_formatter_) {
     currency_formatter_.reset(
         new CurrencyFormatter(currency_code, currency_system, locale_name));
   }
   return currency_formatter_.get();
 }
 
 }  // namespace payments